Embodiments of the invention relate to devices to create access to interior body regions and methods of using the devices.
There are many instances in which a practitioner must access the chest, abdomen, or pelvis, and insert a drainage tube, or chest tube. Examples of these instances include: collapsed lung, lung infection, bleeding in the chest cavity, fluid or air buildup due to other medical conditions or trauma, and prior surgery.
The traditional way of inserting a chest tube begins with the practitioner prepping the side of the body for the chest tube by sterilizing the area. Using a scalpel, the practitioner then makes a small incision (skin nick), between the ribs closest to the desired location in the chest. Then, using a combination of blunt dissection and surgical clamps, the practitioner will slowly open the space and extend it into the chest cavity. Once the practitioner confirms she has reached the desired space, the chest tube is inserted and sutured in place to prevent slippage.
Critics claim that the traditional method of chest tube insertion is barbaric and does not take advantage of advances in technology that can make the insertion process safer and more effective. Some companies have designed devices, called trocars, to facilitate safer and easier chest tube placement without using multiple, separate components.
Many groups of trocars include a combination of a safety needle, an obturator and a dilator. The doctor advances the device against the skin and interior body regions using the safety needle. As the doctor advances the device through the body, the obturator expands the pathway created by the safety needle. When the device reaches the desired area, the practitioner removes the safety needle and the obturator from the dilator, leaving the dilator in place. The practitioner then pushes the chest tube through the dilator and removes the dilator, leaving the chest tube in the desired location.
Problems arise with these types of trocars, however, because the obturator does not actually work very well in expanding the pathway created by the relatively small safety needle. The skin provides a tough membrane that resists expansion, and additional skin nicks (using a separate scalpel) are required around the safety needle to allow the obturator to properly expand the skin layer and continue to penetrate deeper into the body.
To address this issue, other groups of trocars employ a retractable blade instead of a safety needle. The blade is used to create a larger skin nick and advance through other tissues as needed until reaching the desired location. The obturator easily expands the pathway as it passes through the skin layer while the practitioner advances the device, and then the blade is retracted and the blade/obturator combination is removed, leaving the dilator in place for the chest tube.
While these groups of trocars address the issue of requiring an additional scalpel to allow the obturator to expand the skin layer, they do not include the safety needle that prevents the doctor from progressing too quickly or too far and causing harm to the patient. Without the safety needle as part of the system, the patient is at a greater risk of complications.
Other groups of trocars include a fixed blade with an obturator with a retractable shield that can expose the blade when the user presses the shield against the skin. The blade creates a larger skin nick, and when the blade reaches an area of lower resistance, the shield automatically advances, covering the blade. Presuming that the area of lower resistance is the desired location, the user removes the blade/obturator combination, leaving the dilator in place for the chest tube.
While these groups of trocars address the issue of providing a safe way to advance the blade into the desired location, they do not provide a way for a user to verify the trocar is in the correct location by aspirating a fluid sample prior to inserting a chest tube. Without confirming the location of the device before chest tube placement, the patient is at greater risk of complications.
What is needed in the market is an all-in-one trocar device that provides the ability to create a skin nick, maintain safety, and aspirate fluid as the device is inserted deeper into the body, while quickly accessing the desired location for chest tube placement.